Berg says that Africa needs to build its local technical capacity if its going to be able to locally, and sustainably, address the continent’s profound health issues. So, he helped create the Rural Technology Lab to train the continent’s first generation of programmers. They are learning to build community initiatives by leveraging the exploding popularity of mobile phones with technologies like RapidSMS.

With the help of this lab and the MillenniumVillages Project, Berg has created ChildCount+, a mobile-phone-based health platform. The project works with community health care workers to ensure that mothers and their children are part of community health systems. By using basic SMS messages, communities are able to register patients as well as track their health in a community patient registry. The pilot program has already registered more than 10,000 kids and 5,000 mothers.

OK Go closed Friday’s session with a brief talk about the current state of the music industry and how they’ve managed to succeed around it thanks to video, content-sharing and being able to put performance back into the musical experience. “Now that the music ‘industry’ has kind of imploded,” said Kulash, “videos no longer have to be ads. They can be more like art.”

The band played several acoustic songs, showed an amazing video starring a bunch of rescued dogs, got the crowd to sing along with them and rocked a lovely set of handbells. Here’s a little video of the bell song shot by a slightly over-caffeinated yours truly from the best seat in the house:

And just because it’s super cute, here’s a video of the slightly star-struck Kulash talking to Kermit the Frog about ping-pong and recording a cover of Muppet music.

The XTeam’s amazing run through the semi-finals brought the West Philadelphia High School students who make up the team, their teacher/coaches, and their mentor Simon Hauger much deserved attention and accolades (they even got props from President Obama).

And while winning the prize would have been awesome, the program’s real value is in the way it has changed team members’ educational experience.

Hauger and team co-captain Azeem Hill, a senior at West Philly, took the stage Saturday to share the XTeam story and offer insights they’ve gained over the years. Hauger, who came to teaching from a career in engineering, started the team as an afterschool project for students who wanted a hands-on science experience.

If there’s one thing PopTech attendees enjoy almost as much as connecting with one another, it’s reading. The intensity of the sessions, the opportunity to share ideas, and the sheer number of people you meet can be overwhelming during conference week. You find yourself in need of occasional solitary, quiet moments, wanting to take an even deeper dive into some of the things you’ve been learning.

Lucky for us, PopTech has an excellent, on-site at the Opera House, albeit temporary, bookstore. Set up and run especially for the conference by the good folks at local booksellers Owl & Turtle Bookshop, the store packs in a wide selection of books from PopTech presenters, attendees and community members both past and present.

We had a chance to chat with Joseph Barber, manager of the Owl & Turtle, in between his very brisk sales. Have a listen and find out who’s hot and what he’s been reading.

Make It Right’s Tom Darden said he’s used to seeing looks of disappointment when he takes the stage instead of Brad Pitt, but maybe he’s selling himself short. His passion for the organization’s green building project in New Orlean’s Ninth Ward is obvious and he’s a commited activist. Besides, it’s the homes themselves that are the real stars and, honestly, who doesn’t love the Big Easy?

Darden joined Pitt when the actor launched Make It Right in the aftermath of Hurricane Katrina. What started as a three-week volunteer mission turned into a full-time job for Darden who is working with a team of world-class architects and designers to build 150 completely green (and conceptually stunning) homes for residents of one the city’s hardest hit areas.

Darden’s presentation at Friday’s conference was at times an emotional one. Whether choking up when recalling a MIR homeowner donating his energy savings back to the organization or showing a flash of righteous indignation at criticism of the added cost of cutting-edge design, Darden wears his emotions on his sleeve, which seems appropriate given the stakes. Make It Right wants to rebuild the Ninth Ward, rebuild it green, and rebuild it beautiful.

“The symbolism of rebuilding the Ninth Ward sends a national message,” he said. “What will it take to get green designers and builders to build these kinds of homes on a national level?”

Innovating new ways to drive down costs of building the LEED Platinum, cradle-to-cradle homes is a big part of what makes Make It Right a leader in the green building movement. Steep initial costs have slowly declined over time as builders, designers, and architects have found more efficient ways to meet the rigorous LEED standards. For example, Darden showed a wireless light switch that eliminates about 70% of electrical costs in initial building.

Building them green is not all that matters – the homes have to also be able to withstand flooding. Most of the homes are raised and, in one case, the house actually floats. Darden also showed off a new duplex design and one for a new multi-family building, evidence of Make It Right’s plans for scaling up in the future.

Darden believes the work they’ve done in New Orleans has far-reaching implications. “We think that this could really roll out beyond New Orleans to other markets around the US,” Darden said. “At Make It Right, we don’t think it should take a disaster to make green building available and affordable.”

When you’re writing up a post about the guy who refuted Michael Pollan’s now infamous PopTech quote about vegans and hummers, you don’t really want to get the facts wrong. PopTech Science Fellow Gidon Eshel is a statistician who grew up working on a dairy farm in an Israeli Kibbutz: a rather curious combination that’s led to a deep knowledge of how what we choose to eat affects our planet.

Last year, when journalist Adam Pasick of New York Magazine questioned the math behind Pollan’s on-stage, rapidly re-tweeted, statement that “A vegan in a hummer has a lighter carbon footprint than a beef-eater in a Prius.”, it was Eshel’s phone that rang for an answer. As Pollan himself quickly admitted, that statement, while arresting, was not correct. And it was Pollan who suggested that Eshel be a presenter at this year’s PopTech, perhaps as a sort of virtual mea culpa.

Facts aside, Pollan did raise a important point about food choice. Using some simple math, Eshel showed the PopTech audience how a meat-based diet far exceeds the carbon emissions of a plant-based diet, and calls most people’s usual way of eating MAD (actually an acronym Mean American Diet). His recommendation is to eat plants, avoid animal products, and favor laws that promote the first and second suggestions.

The biologist and 2010 Science and Public Leadership Fellow studies the origins of biological complexity and diversity. Dunn is fascinated by deep-sea superorganisms known as siphonophores, which can reach more than 100 feet long. Challenging the definitions of individuality, siphonophores function as a single animal, yet comprise thousands of organisms that are genetically identical but function in different ways. Dunn explores how evolutionary pressures have acted on the siphonophore itself, and whether natural selection is also acting upon individual organisms within it.

During the recent Gulf of Mexico oil spill, 800 skimmers were deployed to recover oil from the water’s surface. Through this method, only three percent of the oil was collected. Because the boats need to collect and then separate oil from water but return to shore to do so, it’s an inefficient process.

So what if there were a way to create an inexpensive, scale-able, and self-organizing system to address this problem?

Carlo Ratti and his team at MIT’s SENSEable City Lab took on this challenge. They were looking to create a system of small units that could extract oil from the water’s surface onsite, collect energy from the sun to continue the process and finally, burn it off. They began by working with some material, created by an MIT professor, which separates and collects oil and leaves water behind. They then collaborated with the ocean engineering department at MIT to create a prototype that works like a conveyor belt rolling on the surface of the earth but nimble enough to adjust to waves. With small and large oil spills happening all the time (unfortunately), let’s hope they start producing this model for use in the near future.

That’s how 2010 Social Innovation Fellow Brooke Betts Farrell described the stench of this country’s garbage piles. The amount of resources – money, energy, land, water — that go into dealing with the things we throw away is staggering. Her idea is simple – she wants her company RecycleMatch to be the eBay of trash. Take polyester scraps from the clothing manufacturer and sell them as seat stuffing to the chair manufacturer; make bags out of billboards. Match those who have waste with those who need it.

“Recycling in this country is inefficient. Only about 30% of what we throw away is recyclable,” Farrell said. “That’s not good enough. I want companies to see their waste as a resource.”